Last April, New England Patriots head coach Bill Belichick took a chance on an enigma in Rutgers safety Duron Harmon. A projected Day 3 or priority free-agent prospect, Harmon’s name was instead called at pick 91 overall – just eight slots after his Scarlet Knight teammate Logan Ryan.

The selection carried an onslaught of questions at the time, and many of those questions still remain. But as the weeks have progressed, so has the 22-year-old’s role in the Patriots secondary. By the end of August, the 6’1”, 205-pounder was able to eclipse 2012 second-rounder Tavon Wilson on the depth chart, playing dime defensive back. And over the last three games, Harmon’s “Money” duties have parlayed into more consistent relief reps at both free and strong safety.

Yet with 8:38 left in the third quarter of New England’s Week 9 tilt versus the Pittsburgh Steelers, Harmon’s responsibilities expanded once more. It was then that starting strong safety Steve Gregory departed with a broken thumb and was replaced by No. 30 for the duration.

By the time the Patriots had defeated Pittsburgh 55-31, Harmon had logged a career-high 39 snaps in the defensive backfield. In the process, he tallied four tackles, a pass deflection and an interception. The rookie showed growing pains as well as promise, but both sides of the ledger were worthwhile for his development.

And his development will monitored closely with Gregory expected to miss a few weeks. In light of that, here is a notebook review of Harmon’s Nov. 3 performance.

Negatives

On five-wide set in red zone, Harmon drops back, watching Steelers flanker Antonio Brown from a distance. The cushion allows the wideout to undercut Patriots cornerback Alfonzo Dennard on a slant route, netting an eight-yard reception before Harmon makes the tackle.

Harmon reacting to an Antonio Brown quick slant.

Opposite “10” personnel down in the red zone, Harmon – the low safety – steps back as Brown runs a crossing route underneath. The pattern forces Harmon to trace into a wall of linebackers. The pass, however, is thrown away from the safety’s vicinity for a touchdown to wide receiver Jerricho Cotchery.

A play after making a run stop, Harmon focuses on the halfback and bites on a play-action fake. Vacating one half of the second level, Harmon sprints towards the line as Roethlisberger rolls out right to hit Cotchery on a 16-yard inside-out corner route beyond the press of Ryan.

Harmon zeroing in on a play-action fake.

Neutralities

In two-deep alignment, Harmon drifts back approximately 30 yards from the quarterback’s release point. The cautious movement creates an opportunity for Roethlisberger to target Brown on a speed-release vertical route outside the single coverage of Patriots cornerback Kyle Arrington. Nevertheless, Harmon is able to read the cues of the passer’s trunk rotation and approach the ball’s destination simultaneous to the throw. The pass falls incomplete.

Helping contain the big-play ability of Brown on a stutter streak – behind the press of Dennard in the red zone – prevents Harmon from spying on the underneath. In turn, Roethlisberger is able to find Cotchery on a slant inside nickelback Marquice Cole. Harmon retreats to his initial starting point and dips down to close off the catch-and-run after 14 yards.

Harmon helping overhead on an Antonio Brown vertical route.

Setting up five yards from the line of scrimmage near the goal line, Harmon tries to find a medium in coverage between Brown’s “sluggo” route and tight end Heath Miller’s post route. He commits to assisting the zone on Brown until he finds Miller crossing through his peripherals. That sight causes him to backpedal away from Brown, who then waves his hands, signaling for the ball. Roethlisberger opts for neither option, throwing an incomplete pass out left towards wide receiver Emmanuel Sanders.

Down on the six-yard line, the Steelers send trips left and Brown as the lone Steeler out right. Harmon huddles close to the box, and assumes the inside coverage on Brown’s post while Dennard assumes the outside. Off the snap, the two Patriots defenders blanket Brown, albeit with Harmon with his back to the ball. The tandem takes one target out of the play but cannot contest Cotchery running a dig route across the middle against linebacker Brandon Spikes. The result is a touchdown.

Positives

Harmon is decisive in providing help on Sanders in the slot against Dennard, leaving quarterback Ben Roethlisberger to throw out of bounds beyond tailback Le’Veon Bell and the single coverage of linebacker Dont’a Hightower down the right sideline.

Facing “11” personnel with Roethlisberger in shotgun and Bell at his left hip pocket, Harmon diagnoses the draw handoff from two-deep safety and seals off play from front side. Good display of reacting to the run and finishing downhill.

Harmon approaching a Le’Veon Bell draw.

Decisive from deep safety, veering from the hashes to the numbers, tracking Brown’s double-move corner route over top from Arrington. The downfield assistance makes Roethlisberger look elsewhere.

Playing high, Harmon sees Roethlisberger’s front foot angle towards the right sideline as he steps into the pocket. In turn, the safety shuffles to the near numbers. The unit’s pass coverage aids the five-man rush and yields a sack.

Roethlisberger finds an opening in the flat, as Brown’s curl route creates separation. The route-runner escapes a missed tackle from Dennard, and Harmon zeros in from five yards inside the numbers to push Brown out of bounds after a 13-yard gain – saving a potential touchdown.

With a trio left and a duo out right, Pittsburgh’s Bell runs a wheel route outside of Brown’s in route down the right sideline. The meshing leaves New England linebacker Dane Fletcher shadowing the tailback. Roethlisberger throws into that matchup, and Harmon travels from the end zone to disrupt the ball, using closing speed and a lowered pad level to turn Bell’s bobble into an incompletion.

Harmon closing in on a Ben Roethlisberger pass to the boundary.

The Steelers facilitate an “11” grouping at midfield, with Harmon playing 20 yards back from Cole and Dennard’s man across from Cotchery and Brown. As the shotgun snap is handled, the two pass-catchers run verts on down the left half. Roethlisberger decides to preemptively throw outside Brown in a miscommunication, and Harmon’s second interception in two games is the byproduct. On his runback, Harmon showcases adept vision, curving in and around two Pittsburgh tacklers before his 42-yard return is halted.

Harmon intercepting a Ben Roethisberger throw from deep coverage.

Overview

Harmon’s performance against Pittsburgh left an encouraging impression. The third-round choice didn’t look out of place next to free safety Devin McCourty. He looked patient, letting the play stay in front of him. From there, he was able make judicious decisions based on what he diagnosed.

Now the newcomer was not perfect; there were instances of hesitation when it came to delegating multiple receivers, and there were overreactions when it came to sensing the run. But on second glance, Harmon did not appear to make the definitive mistakes you expect to see from a young defensive back thrust into the lineup.

He appeared well-versed for the opportunity.

“To go out there and be prepared to play those type of minutes, that’s what made it even better,” Harmon said (h/t MassLive.com’s Nick Underhill). “Not going out there scared or nervous because I didn’t prepare, but going out there with confidence because I prepared like I was the starter.”

Harmon will be the starter until Gregory returns. And although the eight-game pro doesn’t have the experience of the eight-season pro he’s replacing, he’s quickly gaining it.

There were teams that had interest in him. You don’t rank players based on where you think other teams will rank them. You don’t rank players by the opinion of the magazine printers. 3rd round is not too high for a guy you think can be groomed to start in your system. They drafted him because they felt he can starter in their system.

I agree. Where Bill drafted him is not Harmon’s fault. But I still can’t get over using a third round pick on him [when he would have been around later] a year after using a second round pick on a guy who’s probably #50 or 51 on your roster.